1In medium bowl, mash avocado. Stir in cream cheese, cumin, garlic powder, salt and pepper. Stir in tomatoes and chiles.
2Sprinkle 3/4 cup of the Monterey Jack cheese on 4 of the tortillas. Top each with turkey slice. Spread avocado mixture over turkey. Top with remaining turkey slices. Sprinkle with 3/4 cup of the Cheddar cheese. Top with remaining tortillas.
3In 12-inch skillet, melt 1/2 tablespoon of the butter over medium heat. Add 1 quesadilla; cook 2 to 4 minutes, turning once, until golden brown. Repeat with remaining butter and quesadillas. Garnish with remaining Monterey Jack and Cheddar cheeses. Top each with olive slice.